Level shifter circuits are used for transmitting a signal from a first region of an integrated circuit having a first supply voltage to a second region of an integrated circuit having a second supply voltage. As many devices in which integrated circuits are used are powered by batteries, power consumption of such devices and therefore of such integrated circuits is a parameter that is very important. Furthermore, as applications run on such devices are more and more demanding, also speed is an important parameter.
U.S. Pat. No. 7,511,553 relates to a level shifter. An input stage comprises a current mirror for discharging switches at an output stage of the level shifter.
U.S. Pat. No. 7,474,138 relates to a level shifter. The circuit comprises two complementary input stages. Each input stage comprises a current source controlled by an input and an output signal. The input stages control two cross-coupled inverters, each input stage controls another inverter. One of the control effects is the current provided by the current sources being copied to the output stages.